The present invention has essentially for a subject matter an improved pressure reducer for use in plants for the distribution of compressed or liquefied gas such as town gas, butane gas, propane gas, etc.
Use has already being made, in domestic plants supplied with combustible gas, of pressure reducers of the type including essentially a casing with gas inlet and outlet connections, a cover mounted on the said casing, and a manometric membrane held between the casing and on the cover, and on the two faces of which acts the pressure of the gas to be controlled and an ajustment spring, respectively.
In such pressure reducers, the manometric membrane is ususally coupled to a linkage, a lever or the like adapted to actuate a valve closure opposite a gas inlet port into the pressure reducer casing. Thus, the flow of the gas into the pressure reducer can be cut in case of gas flow cut-off or in case of malfunction.
However, in the known pressure reducers of the above type, the linkage coupled to the membrane and carrying the valve closure increases the number of parts to be provided within the pressure reducer and necessarily increases the difficulties in assembling the apparatus as well as the space occupied thereby, thus sometimes making difficult its mounting on gas conduits which are difficult of access. Also, the mechanical complexity of such pressure reducers makes them expensive and, as can be readily understood, their reliability is the more reduced as the parts which they contain are more numerous.